a7p 1.0.2

Simple python3 wrapper for .a7p files

Simple python3 wrapper for .a7p files

.a7p is the most common ballistic profile format for the latest Archer thermal vision devices

Table of Contents

• Installation
• Usage
• Dimensions
• Gallery of .a7p ballistic profiles
• .a7p ballistic profiles CDN

Installation

As CLI tool

# with `uv`
uv tool install a7p

# with `pipx`
pipx install a7p

Installation to your project:

# with `uv`
uv add a7p

# with `pip`
pip install a7p

[!TIP] You can install orjson - the fast Rust-based JSON encoding backend To install it together with a7p use optional dependencies group a7p[orjson]

Usage

CLI-tool

a7p -h
usage: a7p 1.0.0b3 [-h] [-V] [-r] [-F] [--unsafe] [--verbose] [--recover] [-zd ZERO_DISTANCE] [-d {subsonic,low,medium,long,ultra}] [-zs ZERO_SYNC | -zo X_OFFSET Y_OFFSET] path

positional arguments:
  path                  Specify the path to the directory or a .a7p file to process.

options:
  -h, --help            show this help message and exit
  -V, --version         Display the current version of the tool.
  -r, --recursive       Recursively process files in the specified directory.
  -F, --force           Force saving changes without confirmation.
  --unsafe              Skip data validation (use with caution).

Single file specific options:
  --verbose             Enable verbose output for detailed logs. This option is only allowed for a single file.
  --recover             Attempt to recover from errors found in a file. This option is only allowed for a single file.

Distances:
  -zd ZERO_DISTANCE, --zero-distance ZERO_DISTANCE
                        Set the zero distance in meters.
  -d {subsonic,low,medium,long,ultra}, --distances {subsonic,low,medium,long,ultra}
                        Specify the distance range: 'subsonic', 'low', 'medium', 'long', or 'ultra'.

Zeroing:
  -zs ZERO_SYNC, --zero-sync ZERO_SYNC
                        Synchronize zero using a specified configuration file.
  -zo X_OFFSET Y_OFFSET, --zero-offset X_OFFSET Y_OFFSET
                        Set the offset for zeroing in clicks (X_OFFSET and Y_OFFSET).
                        
Advanced:
  --spec-validator      Use spec-based validator (deprecated).
  --protovalidate       Use protovalidate (deprecated).

Use as imported module

import logging
import a7p
from a7p import exceptions, A7PFactory

# open file in binary mode
with open('data/test.a7p', 'rb') as fp:
    # read data from file
    try:
        payload = a7p.load(fp)
    except exceptions.A7PDataError as exc:  # raises if md5 crc not match
        logging.error(exc)

# accessing attributes as for default protobuf payload
profile_name = payload.profile.profile_name

# data conversion to common types
payload_json = a7p.to_json(payload)
payload_dict = a7p.to_dict(payload)
from_json = a7p.from_json(payload_json)
from_dict = a7p.from_dict(payload_dict)

# saving builded profile
with open('data/test.a7p', 'rb') as fp:
    a7p.dump(payload, fp)

# creating a new a7p Payload
payload = A7PFactory(
    meta=A7PFactory.Meta(
        name="test profile name",
    ),
    bullet=A7PFactory.Bullet(
        weight=175,
        length=0.9
    ),
    distances=A7PFactory.DistanceTable.LONG_RANGE
)
with open('data/test.a7p', 'wb') as fp:
    a7p.dump(payload, fp)

Dimensions

To obtain values from an .a7p profile in the desired units, you need to divide them by the multiplier. For the reverse operation, you need to perform the inverse operation and convert to an integer.

key	unit	multiplier	desc
sc_height	mm	1	sight height in mm
r_twist	inch	100	positive twist value
c_zero_temperature	C	1	temperature at c_muzzle_velocity
c_muzzle_velocity	mps	10	muzzle velocity at c_zero_temperature
c_t_coeff	%/15C	1000	temperature sensitivity
c_zero_distance_idx		10	index of zero distance from distances table
c_zero_air_temperature	C	1	air temperature at zero
c_zero_air_pressure	hPa	10	air pressure at zero
c_zero_air_humidity	%	1	air humidity at zero
c_zero_p_temperature	C	1	powder temperature at zero
c_zero_w_pitch	deg	1	zeroing look angle
b_diameter	inch	1000	bullet diameter
b_weight	grain	10	bullet weight
b_length	inch	1000	bullet length
twist_dir	RIGHT|LEFT		twist direction
bc_type	G1|G7|CUSTOM		g-func type
distances	m	100	distances table in m
zero_x		-1000	zeroing h-clicks for specific device
zero_y		1000	zeroing v-clicks for specific device
coef_rows.bc_cd (G1/G7)		10000	bc coefficient for mv
coef_rows.mv (G1/G7)	mps	10	mv for bc provided
coef_rows.bc_cd (CUSTOM)		10000	drag coefficient (Cd)
coef_rows.mv (CUSTOM)	mach	10	speed in mach